By the end of the day, more than 500 young women and men will be up for sale in San Diego through online ads promoting illegal commercial sex. And that’s only on one website known for advertising the sex trafficking of minors.

These heinous crimes are not just taking place in the shadows of cyberspace. They’re happening at businesses, hotels, schools, parks, malls, bus stops and other public venues across our city — often in plain sight.

In fact, the Federal Bureau of Investigation (FBI) ranks San Diego among the top areas for child prostitution in the United States. Simply put, “America’s Finest City” cannot afford to bury its head in the sand when it comes to human trafficking. It’s real, it’s close to home and it requires the entire community coming together to help protect the most vulnerable among us.

That’s why there’s a growing chorus of businesses and nonprofits like Cubic Corp. and Project Concern International (PCI) joining forces to raise public awareness about this issue, prevent the exploitation of children, and address factors that contribute to the demand.

By raking in an annual revenue of $810 million, sex trafficking is one of San Diego’s largest underground economies — second only to drug trafficking. Perhaps even more staggering is that it’s largely made possible by “pimps” and “buyers” using office resources on company time.

For instance, did you know that 75 percent of transactions for illegal sex are made online and often times during work hours, with a peak time being between 10 a.m. and noon? After posting one single online ad for underage sex in San Diego to catch potential buyers, there were over 700 responses in one week alone.

According to an ongoing study by the Organization of Prostitution Survivors and Businesses Ending Slavery & Trafficking (BEST), 63 percent of prostituted people said that they met clients on company properties.

Recognizing that local employers can help put a stop to this alarming trend, PCI and Cubic have partnered to form a coalition called Business Alliance Against Trafficking. This developing coalition of San Diego-based corporations will focus on implementing best practices that prevent the exploitation of human beings as commodities. Example actions include: adopting policies that prohibit sex buying; educating employees on the issue; supporting local anti-trafficking organizations; and creating safe job opportunities for survivors.

Although it’s difficult to imagine children and adolescents at the center of this atrocious industry, the average age of entry for San Diego’s sex trafficking victims is 16 years old. Many already have a history of abuse and homelessness and are often recruited through family members and friends looking to make a profit.

For example, Jessica was only 8 years old when her mother started selling her to men in order to support her drug habit. By the time she turned 13 years old, Jessica was trafficked at the hands of a pimp. In addition to turning to drugs and contracting sexually transmitted diseases, she also became pregnant by her trafficker. He beat the young woman so badly that she had a miscarriage.

While Jessica is now thriving and her pimp ended up in prison, her story is among thousands of survivor accounts that underscore the importance of empowering youth in San Diego to say “no more” — ending the demand and garnering support across the city to stop this modern-day slavery in its tracks.

Partners like the Boys and Girls Club of Greater San Diego and local San Diego schools offer the Girls Only! program to promote self-esteem and develop life skills in young girls who are at risk of commercial sexual exploitation. Plans are underway to expand this programming to other youth service locations throughout San Diego County and to include boys between the ages of 8 to 15.

The District Attorney’s Office, local law enforcement and the FBI are working together with local nonprofits to find perpetrators and bring them to justice. In addition, the Airport Authority collaborates regularly with area agencies involved in the prevention of sex trafficking.

At San Diego International Airport, signage is posted at security checkpoints. And Southwest Airlines is a key player in monitoring young girls and boys who may be trafficked to and from our city.

San Diego has an important opportunity to be a leader in the fight against human trafficking, especially given our proximity to the U.S. border and the constant movement of people in and out of our area. We are doing our part to end this horrific practice, and we encourage all our citizens to take notice and protect our children.

Hessler-Radelet is the president & CEO of Project Concern International, and Feldmann is the president & CEO of Cubic Corp.